From ABC News (via AP), reports of Avandia side effects (including heart attacks, deaths and hospitalizations) tripled in the month following the New England Journal of Medicine's report on the drug's safety. For example, only 5 heart attacks were reported in the 35 days prior to the study's announcement, while 90 heart attacks were reported in the same period following the study.

The story notes:

The sudden spike is a sign that doctors probably were unaware of the drug's possible role in their patients' heart problems and therefore may not have reported many such cases in the past, several experts said.

It also shows the flaws of the safety tracking system and suggests that a better one might have detected a potential problem before the drug had been on the market for eight years.